Suicide gene therapy for gastrointestinal tumors using tumor-specific promoters

使用肿瘤特异性启动子进行胃肠道肿瘤的自杀基因治疗

基本信息

批准号：
11671298
负责人：
TAGAWA Masatoshi
金额：
$ 2.24万
依托单位：
Chiba Cancer Center Research Institute
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

项目摘要

Tumor-specific gene expression is important for improved safely and enhanced efficacy of gene therapy for cancer. We then examined promoter regions of the midkine gene which was expressed in tumors but not in normal surrounding tissues or that of the c-erbB-2 and vascular endothelial growth factor gene whose expressions were predominantly found in the tumors of upper gastrointesinal tract and a number of solid tumors, respectively. Our results were as follows. (1)The midkine gene was expressed in 8 out of 14 human esophageal specimens and 14 out of 15 hepatocellular carcinoma specimnens, whereas none of non-tumorous regions of the same patients were negative for the expression. (2)Reporter assays using deletion mutants of the promoter region of the midkine gene showed that the 550-bp fragment was responsible for tumor-specific transcriptional activation. (3)The 250-bp fragment of 5'-upstream region of the c-erbB-2 gene strongly drove the transcription of the fused reporter gene in tumors but not in normal fibroblasts. (4)The 1.2-kb promoter region of the vascular endothelial growth factor gene had a cis-acting element for hypoxic responsiveness. (5)Forced expression of the herpes simplex virus-thymine kinase gene using these linked promoters conferred increased sensitivity of the transfected vells to ganciclovir. (6)The deoxycytidine kinase/ara-C and the uracil phosphoribosyl transferase/5-FU systems were useful for cell killing together with an appropriate promoter.

肿瘤特异性基因表达对于改善癌症基因治疗的安全性和增强疗效非常重要。然后，我们检查了中期因子基因的启动子区域，该基因在肿瘤中表达，但在正常周围组织中不表达，或者检查了c-erbB-2和血管内皮生长因子基因的启动子区域，其表达主要在上胃肠道肿瘤和一些肿瘤中发现。分别是实体瘤。我们的结果如下。 (1)中期因子基因在14例人食管标本中的8例和15例肝细胞癌标本中的14例中表达，而同一患者的非肿瘤区域均未表达阴性。 (2)使用中期因子基因启动子区缺失突变体进行的报告基因检测表明，550 bp的片段负责肿瘤特异性转录激活。 (3)c-erbB-2基因5'上游区域的250bp片段强烈驱动融合报告基因在肿瘤中的转录，但在正常成纤维细胞中则不然。 (4)血管内皮生长因子基因的1.2-kb启动子区域具有低氧反应的顺式作用元件。 (5)使用这些连接的启动子强制表达单纯疱疹病毒胸腺嘧啶激酶基因，使转染的细胞对更昔洛韦的敏感性增加。 (6)脱氧胞苷激酶/ara-C和尿嘧啶磷酸核糖转移酶/5-FU系统与适当的启动子一起可用于细胞杀伤。